[2point4DSM]

2. 90 model year had an air-cooled oil cooler while all the other models afterwards had a coolant-cooled oil cooler which are known to come apart. The problem is the part that the oil filter scews onto loosens and causes the oil filter to back off. Many people have lost a motor/turbo due to this.

Not to mention the the coolant-cooled oil cooler units have a tendency to get squashed and leak internally causing oil and coolant to mix.

Best fix is to upgrade 91+ DSMs to the air-cooled oil cooler units. Still, motors with cams, removed balance shafts, and stiffer motor mounts are not completely immune. Another solution is to add a hose clamp around the filter to help lock it down to the block.